condition mean min max ZT0-3 26.53921666666667 19.709400000000002 34.20525 ZT4-7 23.20045 23.20045 23.20045 ZT8-11 17.71125 17.71125 17.71125 ZT12-15 17.785075 17.0487 18.52145 ZT16-19 24.58115 24.58115 24.58115 ZT20-23 21.9536 21.9536 21.9536